1. Technical Field
This invention relates generally to digital photo storage media such as exists in a digital camera and, in particular, to methods for more efficient storage of digital content in such media.
2. Description of the Related Art
Recently, the computer industry has sought to add computer processing and communications capabilities to devices other than what would normally be considered a traditional computer. Such devices are quite varied and include, for example, personal digital assistants (PDAs), smartphones, cellular phones, desktop screen phones, in-vehicle devices, business organizers (e.g., IBM WorkPad(trademark), PalmPilot(trademark), and the like), peripherals (such as printers, fax machines, and the like), handheld or palmtop computing devices, and the like. For convenience, these devices, as a class, are referred to herein as xe2x80x9cpervasive computingxe2x80x9d clients as they are devices that are designed to be connected to servers in a computer network and used for computing purposes regardless of their location.
Digital cameras are now being proposed as pervasive computing devices. The recent increase in the popularity of digital photography has created a need for improved storage schemes in such devices. Because digital cameras must store images in either RAM or removable media, each with a finite capacity, it is desirable to maximize the amount of photos that can be stored in the camera. To this end, most digital cameras use a compression scheme, such as JPEG, to reduce the size of the photos.
While such compression schemes are quite useful, there remains a need to provide enhanced methods for storing digital photos in digital photo storage media. Preferably, such methods would not require special image processing functions or new compression techniques.
The present invention addresses this problem.
It is a primary object of this invention to maximize the capacity of digital photo storage media such as exists in a digital camera.
It is another primary object of this invention to provide a mechanism that uses lightweight image manipulations, such as clipping, inversion, rotation and reflection, to minimize the total space required to store digital pictures on digital storage media, such as disk or RAM cards.
It is a further object of this invention to maximize digital photo storage media capacity without special image processing functions or new compression techniques.
Another object of this invention is to augment existing compression techniques (e.g., JPEG) in digital cameras to provide for improved storage of digital photos.
Still another more general object of this invention is to provide a novel approach to storing a collection of images in a digital camera in a given manner to maximize storage savings with very little overhead.
Another general object is to provide a digital camera having enhanced photo storage capability.
These and other objects are achieved in a digital camera that includes a lightweight image processing mechanism according to the present invention The mechanism divides up each picture stored in the camera, preferably into equal size subcomponents. The subcomponents from a given set of the photos are then xe2x80x9cquiltedxe2x80x9d together, preferably into one large composite image. Preferably, the subcomponents are stitched together in such a way that maximizes the camera""s existing compression technique. In particular, given subcomponents are selectively transformed (e.g., clipped, inverted, rotated, reflected, and the like), to position the subcomponents as desired. For example, if the camera uses JPEG compression, two predominately blue subcomponents are placed next to each other as JPEG is a compression technique that exploits color redundancies. After the subcomponents are processed, the coordinates of the sectors are indexed and stored so that an individual image can be reconstructed by clipping out its component subcomponents and reassembling the image. With this processing, the more similar the photos in the set, the more compression benefit is achieved.
Thus, preferably the present invention is implemented in a digital camera having a digital storage media and a compression routine for storing digital photos in a compressed formal in the digital storage media. According to the invention, a set of digital photos are processed into subcomponents, which are then collected into a composite image and then applied to the compression routine. The coordinates of the subcomponents within the composite image are then indexed and stored so that the individual photos can be reconstructed.
The foregoing has outlined some of the more pertinent objects and features of the present invention. These objects should be construed to be merely illustrative of some of the more prominent features and applications of the invention. Many other beneficial results can be attained by applying the disclosed invention in a different manner or modifying the invention as will be described. Accordingly, other objects and a fuller understanding of the invention may be had by referring to the following Detailed Description of the Preferred Embodiment.